Process of making chlorates and apparatus therefor.



G. KOLSKY.

PROCESS OF MAKING GHLORATES AND APPARATUS THEREFOR.

APPLICATION FILED APRA, 1913.

Patented Apr. 7, 191i 2 SHEETS-SHEET 1.

Z M62050 r.-

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6. QLJQIL.

G. KOLSKY.

PROCESS OF MAKING GHLORATBS AND APPARATUS THEREFOR.

APPLIOATION FILED APR.4, 1913.

1,092,369. Patented Apr. 7, 191 1 2 SHEETS-SHEET 2.

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"Th 6 L1 Gumqe GEORGE KOLSKY, OF NIAGARA FALLS, NEW YORK.

Specification 01' Letters Patent. Patented Apr, Application med April 4, 1913. Serial No. 758,920.

.rnoonss or MAKING onLonATns AND APPARATUS-THEREFOR.

T '0 all whom it may concern:

Be it known that I, Gnonon KoLsKY, a citizen of the Republic of Switzerland, residing at Niagara Falls, in the county-of Niagaraand State of New York, have invented oer tain newand useful Improvements in Processes 'of- Making Chlorates and Apparatus Therefor, of which the following is a specification. f This invention relates to processes and apparatus for the electrolysis of saline solutions, more particularly for the preparation of chlorates of the alkali metals, and other compounds resulting from the interaction of anodic and cathodic products of electrolysis. I

For a full understanding of the invention,

reference is made to the accompanying drawings, wherein Figure 1 is a central vertical vsection of one form of apparatus embodying the invention; Fig. 2 is a partial horizontal sect-ion thereof on line 11-11 of Fig. 1; Fig. 3 is a vertical longitudinal section of a modified form of apparatus likewise embodying the invention; Fig. 4 is a transverse section on line IVIV of Fig. 3, the anodes being removed; Fig. 5 is a perspective view of one form of anode; and Fig.6 is a similar view of a modified form of anode.

Referring to Figs. 1 and 2, 1 represents a tank or vessel which may be of cast iron, and is preferably of large capacity, usually several hundred allons. 2-is a cover of similar material 1n electrical contact with the body of the vessel. 3, 3 are bars, rods or projecting members of suitable conductive material preferably of cast iron; these bars may be integral with the bottom of the vessel. 4,4 are similar bars or rods, indicated as cast integral with the cover 2. The bars 3, 4, together with the interior. of the vessel or so much thereof as is in contact with the electrolyte, constitute the cathode elements of the electrolytic cell, electrical connection thereto being indicated at 5. 6, 6 represent the anodes, which ma be of copper plated or otherwise covere with platinum. These anodes are rods arranged adjacent and between the cathodes 3, 4 and extending through insulating lates 7 in the cover of the cell, to the ano e bus-bar 8. 9 represents the gaseduction pipe, 10 the liquid draw-ofi, and 11 the su ply-pipe for electrolyte. It will be noted t at the anode and cathode elements are, in this construction, arranged at an inclination to the vertical, and are so dis osed as to'permit the free circulation .of the iquid through an open or grld-hke structure; formed by electrodes of opposite polarity. 'In the'operation of the cell for the preparation of chlorates, for example, hydrogen is liberated at the cathodes 3, 4, and owing to their inclined position escapes therefrom with comparative free- 'dom, rising directly to the surface of the electrolyte. This upward motion of the gas lnduces a strong circulation of the electrolyte along the general lines of flow indicated by the arrows in Fig. 1; and this circulation, in turn, aids in the detachment of the bubbles,

with the result that not only is all polarization of the electrodes avoided, but fresh electrolyte is constantly brought to the field of most intense electrolytic action. *Moreover, under this arrangement the electrolyte flows m quick succession in contact with surfaces of opposite polarity, thereby affording the most favorable condltions for the union of the anode and cathode products of electrolysis. Under these conditions, a very high current-efficiency is assured and it becomes practicable to employ very high current densities, for as will readily be understood, the velocity of'flow of the, liquid increases as the current-densit is increased,

by reason of the increase evolution of hydrogen,

The electrodes have been illustrated, for the sake of clearness and simplicity, as comparatively few in number and disposed in several groups: but it is to be understood that they may be, and preferabl are, disposed in the form of a practical y uninterrupted rid or open cone-shaped structure within t e vessel 1, so as most effectively to,

subject all of the electrolyte to their action. Obviously, the direction and degree of inclination of the electrodes may be varied as desired, without sacrificing the essential purposes of the invention."

As illustrated in Fig. 1, the anodes 6 gradually increase in cross-section toward their lower ends, the cathodes being cylindrical and substantially parallel to the anode. .surfaces. This construction is notessential,

but is desirable as insuring a greater proportionate liberationof gas at points well below the surface of the electrolyte, where its efiiciency in promoting the circulation o the electrolyte is of course higher.

Hit!

Obviously, the electrodes may be arranged otherwise than in the form of a cone. For

example, as shown in Figs. 3, 4, the electrolytic cell may comprise a rectangular tank 1 of concrete or the like, having a cast-iron or other metal cover 2, from which the cathode bars 4 depend, each transverse series of bars forming a comb-like structure as indicated in Fig. 4. 9 indicates the gas outlet, 10 the liquid outlet and 11 the liquid supply-pipe. The cover 2 is slotted as at 12 to receive insulating slabs 13 of concrete or the like, which carry the anodes 6", usually consisting of platinum or platinizedcopper.

Various constructions ofanode may be employed, the essential feature being the provision of an open or grid-like structure, through which the electrolyte may circulate freely. For example, each anode may comprise a series of platinized'copper bars 6 (Fig. 5), set in a lead cap 14, which is connected to the anode bus-bar 15. Or as shown in Fig, 6, the anode may comprise similarly mounted frames 16 of platinized copper, carrying screens 17 of platinum wire.

It is preferred in all cases to incline the electrodes, since a better circulation of electrolyte is thereby obtained, but I do not regard such inclination as essential in every 'case to the practice of my invention, since commercially practicable resultsmay be obtained with electrodes which are either vertically or horizontally disposed, provided the combined electrode structure be such as ductive structure, perforated or not, withhydrogen at the-cathodes, and its upward out seriously interfering with the circulation; and, in general, the apparatus may be variously modified without departing from the spirit of my invention.

The apparatus may be used not only for the reparation of chlorates, but as well for the manufacture of hypochlorites and, in general, of such compounds as result from 1 the interaction of anodic and cathodic products of electrolysis.

In the use of the apparatus for the manufacture of potassium chlorate, it is preferred to subject the considerable body of liquid contained in the vessel to electrolytic action for several hours, or until the ercentage of chlorate has risen to the desired degree, whereupon the liquidis withdrawn and replaced by fresh electrolyte. Under this "mode of operation, there is' no continuous flow of electrolyte into and from the apparatus, and the circulation of the liquid therein is due solely to the evolution of movement therefrom. For the operation of density at the anode surfaces being, say, 160

to 200 amperes per square dcm.

I claim: 1

1. An electrolytic process of producing chlorates or the like, which consists in pass ing an electric current through a suitable electrolyte between electrode surfaces separated only by said electrolyte, and maintaining such evolution of gas at the cathodes as will suffice to induce an active circulation of the electrolyte past the electrodes and effect the depolarization thereof, the lines of flow of the electrolyte passing electrodes of opposite polarity in rapid succession.

2. An electrolytic process of producing chlorates or the like, which consists in passing an electric current through a suitable electrolyte between inclined electrode surfaces separated only by said electrolyte, and maintaining such evolution of gas at the cathodes as will suffice to induce an active circulation of the electrolyte past electrodes of opposite polarity and effect the depolarization thereof.

3. In electrolytic apparatus for the preparation of chlorates or the like, the combination of a vessel and a plurality of electrodes of opposite polarity therein, said electrodes separated only by the electrolyte and dis posed to provide an open or grid-like structure' through which the electrolyte may freely circulate, said electrodes being so arranged that the hydrogen liberated at the cathode will induce a repeated circulation of the electrolyte through said grid-like structure, the lines of flow of the electroly'te passing electrodes of opposite polarity in rapidsuccession.

4, In electrolytic apparatus for the prepain presence of two witnesses.

GEORGE KOLSKY.

Witnesses:

Wmrnm A. Dorms,

WILL H. BLAIN. 

